We had a over a hundred deployed so I did pretty exhaustive analysis. There is no rtc or anything that needs power. The at328p chip used has nonvolatile storage

We had a over a hundred deployed so I did pretty exhaustive analysis. There is no rtc or anything that needs power. The at328p chip used has nonvolatile storage, the battery does not supply power when the power to the thermostat is removed, and the battery keeps a gpio pin on the mcu high. It’s pretty plain.